Dishwashing apparatus having impeller-operated means for controlling water supply



July 31, 1951 E. K. CLARK 2,562,772

DISHWASHING APPARATUS HAVING IMPELLER-OPERATED MEANS FOR CONTROLLING WATER SUPPLY Filed April 14, 1945 2 Sheets-Sheet l wnmzsszs; INVENTOR Q I EARL K. CLARK ATTORNEY July 31, 1951 E. K. CLARK DISHWASHING APPARATUS HAVING IMPELLER-OPERATED MEANS FOR CONTROLLING WATER SUPPLY 2 Sheets-Sheet 2 Filed April 14, 1945 INVENTOR EARL K. CLARK 9% a W ATTORNEY WITNESSES:

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Patented July 31, 195-1 DISHWASHIN G APPAR ATUS HAVING IM- PELLER-OPERATED MEANS FOR CON- TROLLING WATER SUPPLY Earl K. Clark, Mansfield, Ohio, assignor to Westinghouse Electric Corporation, Pa., a corporation of Pennsylv East Pittsburgh, anla Application April 14, 1945, Serial No. 588,381 3 Claims. (Cl. 134-57) My invention relates to washing apparatus, more particularly to apparatus for washing dishes, and it has for an object to provide improved apparatus of this kind.

A further object of the invention is to terminate the delivery of washing water to a washing machine automatically when the level of the water in the machine is at the proper elevation.

A still further object of the invention is to provide an improved dishwasher having a motordriven impeller for the circulation of water in the washer wherein the delivery of the proper amount of water to the washer is automaticallyefiected without the use of metering devices such as, for example, float, flow control or weighing mechanisms.

These and other objects are effected by my invention as will be apparent from the following description and claims taken in connection with the accompanying drawings, forming a part of this application, in which:

Fig. 1 is a sectional view through the lower portion of a dishwasher constructed and arranged in accordance with my invention;

Fig. 2 is an enlarged sectional view of aportion of the apparatus shown in Fig. 1;

Fig. 3 is a sectional view of a switching mechanism shown in Fig. 2 and taken generally along the line III-III thereof;

Fig. 4 is a section of a detail the line IV-IV of Fig. 3;

Fig. 5 is a section taken along the line VV of Fig. 1 and illustrates the means for supporting the driving motor; and

Fig. 6 is a diagram of the electrical connections for the apparatus shown in Figs. 1 to 5, inclusive.

Reference will now be had to the drawing, wherein I have shown my invention applied to a dishwashing machine having a tub or vat 0, the bottom wall H of which is shaped to define a well |2 for a body of washing water. The upper level of the body of Water is indicated by the broken line I3. The central portion of the bottom wall II is provided with an upstanding cylindrical baille M which extends above the Waterline l3 and which encloses the driving shaft l5 of a water-projecting impeller It. The latter is rotated by a motor generally indicated at ll for projecting water upwardly within the vat l0 into contact with dishes (not shown) but which are carried by racks, one of which is diagrammatically shown in broken lines at 18. As the construction and arrangement of the dish-supporting racks l8 within the vat l0 form no part of this invention, further description thereof is deemed unnecessary.

and is taken along The impeller I5 includes a hollow hub portion l8 and a pair of water-projecting vanes or blades 2| which extend outwardly from the hub l3. As shown, the hub I9 is spaced from the baflle It so that the impeller I6 and its shaft l5 may move through a limited range of movement in every direction with respect to the stationary baflle H.

The driving motor I! is supported from the tub In in any well-understood manner but preferably by a flexible mounting arrangement shown in Figs. 1 and 5 and including a generadlly triangular-shaped ring member 22 which is fixed to the tub ID by means of three brackets 23. A trio of brackets 24 are secured to the motor and are arranged within the triangular ring member 22. A resilient supporting member 25 formed of rubber or the like is arranged between each of the brackets 2| and the triangular member 22. Each of the resilient members 25 is provided with a stud 26 which is vulcanized or otherwise secured to the resilient member 25 and which is secured to its respective bracket 24 by a nut 21. Similarly, the opposite end of the resilient member 25 has a stud 28 vulcanized thereto and which is secured to the triangular ring member by a nut if. It will be apparent from the foregoing that the motor is resiliently suspended by the three resilient members 25 and that it is free to vibrate in all modes. which I have shown is disclosed by way of example and it will be understood that the motor I! may be carried by the tub l0 either rigidly or resiliently in any well-known manner.

Washing water is admitted to the tub l0 under control of a suitable electrically-operated valve, generally indicated at 3| and carried by the motor |'I. Preferably, the valve 3| is actuated by a solenoid device 32 which, when energized opens the valve 3| and, conversely, when deenergized, closes the valve ill. The valve 3| is connected by a conduit 33 to a source of hot water and by a resilient conduit 34 to a suitable fitting 35 arranged to discharge the water into the tub Ill.

The drain conduit for the washer is shown at 36 and is connected to a drain outlet fitting 31, the latter being secured to the tub In in any well-understood manner. The discharge of water from the tub to the drain conduit 35 is controlled by a resilient valve 38 formed, for example, of rubber and having an overflow tube 39 secured thereto and extending upwardly in the well l2. The valve 38 and the tube 39 are hollow and the latter is open at the top so that an overflow passage is formed interiorly of the valve 38 and tube 39 in the event that too much water is ad- The resilient supporting means I mitted to the well l2. The valve 38 is opened and closed by a valve stem 4| which is moved upwardly and downwardly by a cam 42. The latter is actuated by a control arm 43 which may be connected to a suitable handle (not shown) arranged in any convenient location on the washing machine.

The motor II which I have shown includes a rotor 44 fixed to the shaft l and which may be a conventional squirrel cage rotor. The frame of the motor I1 is shown at 45 and supports stator laminations, generally indicated at 46 and the windings of the motor are indicated at 41.

In accordance with the invention, the rotor 44, shaft l5 and impeller l6 are so supported that they may move axially as a unit throughout a limited extent for controlling the amount of water supplied to the tub l3; further reference to this operation appearing hereinafter.

The motor shaft i5 is carried by an antifriction thrust bearing of the ball type, as shown at 48, and including a supporting shell 50. The latter is adjustably carried by a screw 49 threaded in an arm 5|, which arm 5| is pivoted, as shown at 52, to a bracket 53. The bracket 53 is secured adjacent its ends by means of screws 54 to the motor frame 45. Turning of the thrust bearing supporting shell 50 relative the screw 49 is prevented by a tongue 50a welded or otherwise secured to the shell 50 and projecting through an opening 50b in the lever 5| (see Figs. 2 and 3).

The pivoted lever 5| is biased upwardly or counterclockwise about its pivot 52 by a spring mechanism which preferably includes a snapover disc spring 55 and a helical compression spring 56. The latter spring 56 engages a collar 51 having upper and lower stop rings 56, 59 formed thereon which are engageable with the bracket 53 and which limit the movement of the springs 55 and 56. An adjustable pin 6| is threaded in the collar 51 and is journaied in the snap-over spring 55; the pin 6| defining a support for the outer or movable end of the lever 5|.

A lock nut 62 maintains the pin 6| in its adjusted position. The support for the snap-over disc 55 is provided by a plurality of upstanding posts 63 which are fixed to the bracket 53 and which have respective slots 64 in which the disc 55 is positioned. The lower end of the compression spring 56 is carried by a cup-shaped washer 65 supported by an adjusting screw 66, the latter being threaded in a saddle 53a carried by the bracket 53. The adjusting screw 66 is maintained in its adjusted position by a lock nut 61.

An electric switch, generally indicated at 68 and best shown in Figs. 2 to 4, inclusive, is carried by the bracket 53. This switch includes a stationary contact 69 carried by the bracket 53 and insulated therefrom, as best shown in Fig. 4. Rivets H may be employed for securing the contact 69 to the bracket 63. The outer end of the contact 69, designated at 12, provides one terminal for the switch structure 63. The movable element of the switch 68 is defined by a resilient spring member 13 having a contact I4 at its movable end and engaging the contact 69. The opposite end of the spring contact 13 is secured by rivets 15 to the bracket 53 and to a terminal 16; the terminal 16, the rivet I5 and the spring contact member 13 being insulated from the bracket 53. The spring contact 13 is biased at all times to its switch-closing position and is actuated to its open position by an insulated projection 'l'l formed on an adjustable screw I8, the latter being threaded in the lever 5| and vat i0. During the filling of the vat with water,

this thrust progressively increases as the head of water is progressively increased within the well l2. During the filling of the well I2 it will be understood that the solenoid 32 is energized so that the valve 3| is open. The thrust progressively increases in intensity due to the progressively increased head of water in the vat and, when the proper head of water is obtained, the thrust predominates over the combined upward bias of the springs 55 and 56 whereupon the shaft l5 moves axially and the lever 5| moves clockwise with snap action to rapidly open the switch 68. Accordingly, the solenoid 32 is deenergized and the water valve 3| is closed for terminating the supply of water to the vat ID.

The switch 68 is maintained open as long as the proper amount of water is contained in the well l2. When the drain valve is opened for removing the water, the reactive thrust on the impeller l6 decreases as the head of water thereon decreases and when the thrust is reduced to a value determined by the adjustment of the springs 55 and 56 the latter move with snap action to swing the lever 5| counterclockwise for the closing of switch 68. As explained hereinafter, a second control switch is connected in series with the solenoid 32, which switch when open prevents energizatin of the solenoid and the admission of water to the well I2. Accordingly, all water may be drained from the well l2 while the impeller l6 continues to operate.

The bias or stress imparted to the disc spring 55 is varied by adjusting the pin BI and the bias of the compression spring 56 is adjusted by the screw 66. Both adjustments may be made at the factory during assembly of the bracket 53 and the parts carried thereby. The reactive thrust or force imparted to the impeller during its operation varies generally lineally or directly with the amount or head of water in the vat l0. Knowing the amount of water to be maintained in the vat and the corresponding value of the thrust imparted to the impeller, and, therefore to the pin 6|, the pin 6| and screw 66 can be readily adjusted to effect the snap-over movement of the spring 55 when subjected to the known thrust. Of course, in making the recited spring adjustments, the weight of the rotating elements and the magnetic pull on the rotor 44 which may be offset from the stator 46 are taken into consideration.

The spring-biasing mechanism shown, is disclosed by way of example and His to be understood that other methods of biasing the impeller IS in opposition to its thrust may be employed.

In Fig. 6, I have shown a wiring diagram for the apparatus disclosed. The supply of power is indicated by line conductors L1 and La and the running and starting windings of the motor at and 8|, respectively. A solenoid operated relay 82 controls energization of the starting winding 8| in a conventional manner, the running winding 80 being in series with a solenoid 83 of the relay l2 and the starting winding 8| in series with contacts 84 of the relay 82. Operation of the motor I! is controlled by a double pole switch 85 connected to the line conductors L1 and L2.

operation of the inlet valve is controlled by a switch 86 preferably of the single pole type and in series with the switch 68. The switches 88 and 86 connect one terminal of the solenoid 32 to the conductor L2 and the other terminal thereof is connected to the conductor L1 through one pole of the two-pole motor switch 85. From the foregoing description it will be apparent that the water valve solenoid 32 can only be energized during operation of the motor I! and that in the event the motor I! is stopped by opening the switch 85, the valve 3| will be closed. The switches 85 and 86 may be manually operated or operated automatically in sequence by a timer motor when applied to a full automatic machine. In any event, the fiow of water to the vat I8 is terminated in response to a predetermined head of water in the vat IS without the attention of the operator.

From the foregoing, it will be apparent that I have provided an improved mechanism for controlling the admission of water to a washing machine having an impeller for circulating the water therein. The amount of water is very closely regulated without the use of water metering mechanisms usually employed for this service such as for example float switches or valves, water weighing mechanisms or constant flow devices. The motor in dishwashers of the type shown is usually operated during the admission of water to the machine so that the water is constantly agitated. Accordingly, water control devices of the float operated type are very erratic in admit ting the proper amount of water to the machine because of the agitation of the body of water.

My improved water control mechanism may be inexpensively manufactured and is, therefore, adaptable for application to low cost manually controlled machines as well as to the higher cost .r'ully automatic machines which carry out a program of washing and rinsing steps without manual attention.

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof.

What I claim is:

1. In dishwashing apparatus, the combination of a. vat for containing variable quantities of water, a rotatable impeller in the lower region of the vat for agitating the water, a motor having a rotor fixed to the impeller for rotating the latter, the axial thrust on said impeller and rotor increasing progressively with increasing quantities of water in the vat, a thrust bearing supporting the rotor, a movable member carrying said thrust bearing and providing for axial movement of the bearing and rotor, means biasing the movable member to a first position in opposition to said thrust and providing for movement of the movable member to a second position in response to a predetermined high thrust value, a snap acting device for rapidly actuating the movable member between its first and second positions and switching means actuated to open and closed positions by said movable member.

2. The combination as claimed in claim 1 including means for adjusting the axial position of said rotor relative to the movable member.

3. In dishwashing apparatus, the combination of a vat for containing the dishes to be washed and a predetermined quantity of water, an electrically-operated valve controlling the admission of water to the vat, a rotatable impeller in the lower region of the vat for agitating the water, a motor having a rotor fixed to the impeller for rotating the latter, the axial thrust on said impeller and rotor increasing progressively with increasing quantities of water in the vat, a thrust bearing supporting the rotor, a movable member carrying said thrust bearing and providing for axial movement of the bearing and rotor, means biasing the movable member to a first position in opposition to said thrust and providing for movement of the movable member to a second position in response to a predetermined high thrust value, a snap-acting device for rapidly actuating the movable member between its first and second positions and a switch controlling said valve and actuated by said movable member, said switch being closed and open in the first and second positions of the movable member, respectively.

EARL K. CLARK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,404,745 Donauer Jan. 31, 1922 1,995,318 Merrill Mar. 26, 1935 2,155,271 Jones Apr. 18, 1939 2,316,570 Dunham Apr. 13, 1943 FOREIGN PATENTS 66 Number Country Date 491,624 Germany Feb. 12, 1930 

